Non-protein nitrogen
Non-protein nitrogen (or NPN) is a term used in animal nutrition to refer collectively to components such as urea, biuret, and ammonia, which are not proteins but can be converted into proteins by microbes in the ruminant stomach. Due to their lower cost compared to plant and animal proteins, their inclusion in a diet can result in economic gain, but at too high levels cause a depression in growth and possible ammonia toxicity, as microbes convert NPN to ammonia first before using that to make protein.
NPN can also be used to artificially raise crude protein values, which are measured based on nitrogen content, as protein is about 16% nitrogen and the only major component of most food which contains nitrogen is protein. The source of NPN is typically a chemical feed additive, or sometimes chicken waste[1][2] and cattle manure.[3][4]
See also
- Nitrogen cycle
- Cyanamide
- Cyanuric acid
- Melamine
- 1,3,5-Triazine
- Triazines
- Chinese protein export contamination
References
- ^ http://jas.fass.org/cgi/reprint/43/1/201.pdf[permanent dead link]
- ^ "Value of Dried Poultry Manure and Urea as Protein Supplements for Sheep Consuming Low Quality Tropical Hay -- Gihad 42 (3): 706 -- Journal of Animal Science". Archived from the original on 2008-10-15. Retrieved 2008-01-15.
- ^ "Nutritional and Economic Value of Animal Excreta -- Smith and Wheeler 48 (1): 144 -- Journal of Animal Science". Archived from the original on 2008-09-06. Retrieved 2008-01-15.
- ^ http://jas.fass.org/cgi/reprint/57/Supplement_2/221.pdf[permanent dead link]